Secondary Hypertension: Novel Insights

It is estimated that 5-10% of hypertensive patients have secondary hypertension. The main causes of secondary hypertension are parenchymal renal disease, primary aldosteronism and renovascular hypertension. The identification of these patients is important because it enables the etiological management of the underlying disease and in some cases leads to blood pressure control without antihypertensive medications. On the other hand, diagnostic evaluation for secondary hypertension often includes complex and expensive tests and should be performed only in patients with a strong clinical suspicion for its presence. If preliminary screening tests suggest the presence of secondary hypertension, these patients should be referred to specialized centers for further diagnostic evaluation and comprehensive management.

Associations of menstrual cycle irregularities with age, obesity and phenotype in patients with polycystic ovary syndrome

OBJECTIVE

Limited data suggest that menstrual cycle abnormalities are more pronounced in younger and more obese patients with polycystic ovary syndrome (PCOS). We aimed to evaluate the association between menstrual cycle pattern and age, obesity and PCOS phenotype in a large population of women with PCOS.

DESIGN

We studied 1,297 women with PCOS and divided them according to: a) age in ≤ 20, 21-30 and > 30 years old, b) body mass index in normal weight, overweight and obese and c) PCOS phenotype in phenotype 1 (anovulation, hyperandrogenemia and polycystic ovaries), 2 (anovulation and hyperandrogenemia without polycystic ovaries), 3 (hyperandrogenemia and polycystic ovaries without anovulation) and 4 (anovulation and polycystic ovaries without hyperandrogenemia).

RESULTS

The proportion of women with regular menstrual cycles progressively increased in the older age groups, being 8.1, 10.5 and 12.7% in women ≤ 20, 21-30 and > 30 years old, respectively (p = 0.037). The proportion of women with regular menstrual cycles did not differ between normal weight and obese women but was higher in overweight women (9.3, 9.4 and 13%, respectively; p = 0.020). The proportion of women with regular cycles alternating with irregular cycles was highest in women with phenotype 4, intermediate in women with phenotype 2 and lowest in women with phenotype 1 (74.3, 69.4 and 61.7%, respectively; p = 0.027).

CONCLUSIONS

Menstrual cycle pattern is more irregular in women with the "classic" PCOS phenotypes than in phenotype 4 but appears to normalize with ageing. On the other hand, obesity does not appear to have an important effect on menstrual cycle pattern in PCOS.

Colesevelam: a new and improved bile acid sequestrant?

Treatment with statins represents an essential component both of primary and secondary cardiovascular prevention strategies. However, a proportion of patients cannot reach low-density lipoprotein cholesterol (LDL-C) targets with the highest tolerable dose of a potent statin or is intolerant to statins. Several treatment options are available for these patients. Colesevelam is a relatively new bile acid sequestrant that decreases serum LDL-C levels. Moreover, colesevelam improves glycemic control and seems to be well-tolerated, at least in short-term studies. Therefore, colesevelam seems to be a useful tool for the management of high-risk patients who cannot achieve LDL-C targets with monotherapy with a potent statin.

Role of lipid-lowering agents in the management of diabetic retinopathy

Diabetic retinopathy affects a substantial proportion of patients with diabetes mellitus (DM) and is the leading cause of blindness in working-aged adults. Even though the incidence of diabetic retinopathy has declined in the last decades, its prevalence increased and is expected to rise further as a result of the increasing incidence of type 2 DM (T2DM) and the longer life expectancy of patients with DM. The pathogenesis of diabetic retinopathy is multifactorial. Some observational studies suggested an association between dyslipidemia and the development and progression of retinopathy in patients with DM but others did not confirm this association. Regarding lipid-lowering agents, studies that evaluated the role of statins in the management of these patients are mostly small and yielded discrepant results. Large randomized studies with statins in patients with T2DM showed no benefit of these agents on diabetic retinopathy but were not designed to address this effect. In contrast, both preclinical data and two large randomized controlled studies, the FIELD and the ACCORD trial, showed that fenofibrate delays the progression of diabetic retinopathy. Even though the mechanisms underpinning this favorable effect are not entirely clear, these findings suggest that fenofibrate might represent a useful tool for the management of diabetic retinopathy.

Novel treatment options for the management of heterozygous familial hypercholesterolemia

Even though statins represent the mainstay of treatment of heterozygous familial hypercholesterolemia (FH), their low-density lipoprotein cholesterol (LDL-C) lowering efficacy is finite and most patients with FH will not achieve LDL-C targets with statin monotherapy. Addition of ezetimibe with or without bile acid sequestrants will also not lead to treatment goals in many of these patients, particularly in those with established cardiovascular disease. In this selected subgroup of the FH population, proprotein convertase subtilisin-kexin type 9 (PCSK9) inhibitors provide substantial reductions in LDL-C levels, reduce cardiovascular morbidity and appear to be safe. Mipomersen, an antisense single-strand oligonucleotide that inhibits the production of apoB by binding to the mRNA that encodes the synthesis of apoB, and lomitapide, an inhibitor of microsomal triglyceride transfer protein, also reduce LDL-C levels but are currently indicated only for the management of homozygous FH. Areas covered: In the present review, the role of PCSK9 inhibitors, mipomersen and lomitapide in the management of FH is briefly discussed. Other LDL-C-lowering agents under evaluation include inclisiran, a small interference RNA molecule that induces long-term inhibition of PSCK9 synthesis, anacetrapib, a cholesterol ester-transfer protein inhibitor, ETC-1002 (bempedoic acid), an inhibitor of adenosine triphosphate citrate lyase, and gemcabene, which reduces hepatic apolipoprotein C-III mRNA. The safety and efficacy of these agents are also reviewed. Expert Commentary: Even though several novel treatment options for heterozygous FH are under development, it remains to be shown whether these treatments will also reduce cardiovascular morbidity in these high-risk patients.

Antisense technology for the prevention or the treatment of cardiovascular disease: the next blockbuster?

Antisense technology might be a gateway to the treatment of diseases by targeting the expression of genes rather than permanently altering them. Thus, there will be fewer ethical concerns. Antisense oligonucleotides (ASO) can alter target gene expression by binding to RNA. Once bound, the ASO either disables or induces the degradation of the target RNA. This technology may be used to treat various conditions (including cancer, diabetes, and hypertension, as well as autoimmune and cardiovascular diseases). ASOs are potentially potent, selective and well-tolerated drugs. Mipomersen (ISIS 301012) inhibits human apolipoprotein (apo)B-100 synthesis and lowers circulating apoB and low-density lipoprotein cholesterol levels. ASO technology may provide a spectrum of agents targeting other vascular risk factors or mediators of atherosclerosis.

The clinical significance and primary determinants of hirsutism in patients with polycystic ovary syndrome

OBJECTIVE

Hirsutism is frequently present in patients with polycystic ovary syndrome (PCOS) and is a major sign of hyperandrogenism. However, other disorders frequently present in PCOS, particularly abdominal obesity and insulin resistance (IR), have also been implicated in the development of hirsutism in this population but relevant data are limited. We aimed to define the determinants of the presence of hirsutism in PCOS.

DESIGN

Observational study.

METHODS

We studied 1297 patients with PCOS (age 24.3±5.8 years, BMI 26.8±6.9 kg/m(2)). Hirsutism was defined as a modified Ferriman-Gallwey score ≥8.

RESULTS

Women with hirsutism were younger, had greater BMI, and had higher levels of circulating androgens than women without hirsutism; markers of IR did not differ between the two groups after adjustment for age and BMI. The prevalence of hirsutism progressively declined with age, was lower in normal-weight women than in overweight and obese women, and was comparably prevalent in the hyperandrogenemic phenotypes of PCOS. In binary logistic regression analysis, independent predictors of the presence of hirsutism were younger age, larger waist circumference (W), and higher serum testosterone levels. In stepwise linear regression analysis, the Ferriman-Gallwey score independently correlated with age, W, free androgen index, and serum Δ4-androstenedione and DHEAS levels.

CONCLUSIONS

Besides hyperandrogenemia, abdominal obesity, and young age are independently associated with the presence of hirsutism. In contrast, the relationship between IR and hirsutism appears to be mediated by the more severe obesity of insulin-resistant patients with PCOS.

Comparative effects of more versus less aggressive treatment with statins on the long-term outcome of patients with acute ischemic stroke

BACKGROUND AND AIMS

There are no studies that compared the effects of different intensities of statin treatment on the long-term outcome of patients with recent ischemic stroke. We aimed to evaluate these effects.

METHODS

We prospectively studied 436 consecutive patients who were discharged after acute ischemic stroke (39.2% males, age 78.6 ± 6.7 years). Statin treatment was categorized in equipotent doses of atorvastatin. One year after discharge, the functional status was assessed with the modified Rankin scale (mRS). Adverse outcome was defined as mRS between 2 and 6. The occurrence of ischemic stroke, myocardial infarction and death was recorded.

RESULT

Adverse outcome rates were lower in patients treated with atorvastatin 20 mg/day or more potent doses of statins than in patients treated with atorvastatin 10 mg/day (63.5, 38.2 and 48.2%, respectively; p = 0.004). In binary logistic regression analysis, independent predictors of adverse outcome were the mRS at discharge (relative risk (RR) 2.33, 95% confidence interval (CI) 1.77-3.07, p < 0.001) whereas more aggressive treatment with statins independently predicted favorable outcome (atorvastatin 20 vs. 10 mg/day, RR 0.30, 95% CI 0.11-0.87, p = 0.026; atorvastatin 40 mg/day or more potent dose of statins vs. atorvastatin 10 mg/day, RR 1.66, 95% CI 0.62-4.44, p = NS). The incidence of cardiovascular events and all-cause mortality showed a trend for being lower in patients treated with atorvastatin 40-80 mg/day or rosuvastatin 10-40 mg/day than in those treated with less potent doses of statins.

CONCLUSION

More aggressive statin treatment improves the long-term functional outcome of patients with acute ischemic stroke more than less aggressive treatment.

Prior treatment with dipeptidyl peptidase 4 inhibitors is associated with better functional outcome and lower in-hospital mortality in patients with type 2 diabetes mellitus admitted with acute ischaemic stroke

It is unclear whether prior antidiabetic treatment affects stroke severity and outcome. To evaluate this association, we prospectively studied all patients who were admitted in our Department with acute ischaemic stroke (n = 378, mean age = 78.8 ± 6.5 years). The severity of stroke was assessed at admission with the National Institutes of Health Stroke Scale. The outcome was assessed with the modified Rankin Scale at discharge and with in-hospital mortality. A total of 123 patients had type 2 diabetes mellitus. At admission, there was a trend for lower National Institutes of Health Stroke Scale in patients treated with dipeptidyl peptidase 4 inhibitors compared with patients treated with other antidiabetic agents (6.1 ± 7.5 vs 10.0 ± 9.2, respectively; p = 0.079). At discharge, patients treated with dipeptidyl peptidase 4 inhibitors had lower modified Rankin Scale than patients treated with other antidiabetic agents (2.1 ± 1.9 vs 3.2 ± 2.1, respectively; p < 0.05). Patients treated with dipeptidyl peptidase 4 inhibitors also had lower in-hospital mortality than patients treated with other antidiabetic agents (0.0% vs 15.1%, respectively; p < 0.05). In conclusion, prior treatment with dipeptidyl peptidase 4 inhibitors in patients with acute ischaemic stroke appears to be associated with better functional outcome and lower mortality risk.

Effect of lamivudine treatment in patients with decompensated cirrhosis due to anti-HBe positive/HBeAg-negative chronic hepatitis B

Lamivudine has been shown to improve liver function and reduce the need for liver transplantation (LT) in patients with decompensated HBeAg-positive cirrhosis. Nevertheless, there is only limited experience with lamivudine in patients with anti-HBe-positive/HBeAg-negative cirrhosis. The primary aim of this study was to determine whether lamivudine treatment improves liver function and subsequently pre-LT survival or delays or obviates the need for LT in patients with anti-HBe-positive/HBeAg-negative cirrhosis. Between July 1998 and June 2003, 20 consecutive patients awaiting LT were enrolled in the study. All patients showed active viral replication and were treated with lamivudine 100 mg daily. Significant clinical improvement, defined as a decrease in the Child-Pugh-Turcotte score by >or=2 points, was observed in 11 (55%) patients. The median change in the Child-Pugh-Turcotte score was -2 (range -5 to +2). The median time required to achieve a 2-point or greater reduction in Child-Pugh-Turcotte score was 6 months (range 3-12 months). In nine patients (45%), the Child-Pugh-Turcotte score decreased to Collapse

Key Words Collapse

MESH Headings

• Antiviral Agents/therapeutic use
• Female
• Hepatitis B e Antigens/immunology
• Hepatitis B, Chronic/complications
• Hepatitis B, Chronic/drug therapy
• Hepatitis B, Chronic/immunology
• Humans
• Lamivudine/therapeutic use
• Liver Cirrhosis/drug therapy
• Liver Cirrhosis/immunology
• Male
• Middle Aged
• Treatment Outcome

Collapse

Grants Collapse

Collaborators Collapse

Age- and body mass index-related differences in the prevalence of metabolic syndrome in women with polycystic ovary syndrome

AIM

To compare the prevalence of metabolic syndrome (MetS) between women with polycystic ovary syndrome (PCOS) and controls across different age (≤20, 21-30 and 31-39 years old) and body mass index (BMI) (normal weight, overweight and obese) groups.

METHODS

We studied 1223 women with PCOS and 277 BMI-matched controls. The prevalence of MetS in women with PCOS and controls was estimated according to four different MetS definitions.

RESULTS

In subjects ≤20 and 21-30 years old, the prevalence of MetS did not differ between women with PCOS and controls regardless of the MetS definition, even though women with PCOS were more obese than controls in the ≤20 years old group. In subjects 31-39 years old, the prevalence of MetS was higher in women with PCOS than in controls but the former were more obese than controls. The prevalence of MetS did not differ significantly between women with PCOS and controls in any of the BMI groups (normal weight, overweight or obese) regardless of the MetS definition.

CONCLUSION

The prevalence of Mets appears to be primarily determined by obesity and age whereas PCOS per se appears to be a less important contributing factor.

Impact of periampullary diverticula on the outcome and fluoroscopy time in endoscopic retrograde cholangiopancreatography

BACKGROUND

It is unclear whether the presence of periampullary diverticula (PAD) affects technical success and complication rates during endoscopic retrograde cholangiopancreatography (ERCP). Moreover, the impact of PAD on fluoroscopy duration is still unknown. The present study aimed to investigate the success rate and difficulty of common bile duct (CBD) cannulation, post-procedure complications and fluoroscopy duration in patients with and without PAD.

METHODS

Patients from January 2008 to December 2010 with PAD (group A) and without PAD (group B) and similar indications for therapeutic ERCP were prospectively compared. The comparison included patient characteristics, findings of ERCP, and details of procedure and fluoroscopy time. The influence of papilla's location with respect to the diverticulum on procedure was also investigated.

RESULTS

A total of 428 consecutive patients who had undergone therapeutic ERCP for similar indications were divided in two groups according to the presence (group A, 107 patients) or absence (group B, 321 patients) of PAD. The mean age and ASA score of the patients with PAD were significantly higher than those patients without PAD. The main indication was choledocholithiasis. Successful final CBD cannulation was achieved in 97.20% of the patients in group A vs 99.69% in group B (P=0.05). CBD diameter, number of stones and the largest stone size were significantly higher in group A than group B (P<0.001). Complete clearance of the CBD after the first attempt was achieved in 85.86% and 94.75% of the patients in groups A and B, respectively (P=0.03). In both groups, the time needed to complete the procedure and fluoroscopy time was significantly longer in patients with PAD (22.87 vs 18.99 minutes, P<0.001; 76.51 vs 47.42 seconds, P<0.001). There was no significant difference between the two groups in the complication rate. The type of papilla's location with respect to the diverticulum did not influence the total cannulation rate and post-procedure complications.

CONCLUSION

The presence of a PAD does not affect the success rate and complications of therapeutic ERCP in expert hands; however, the fluoroscopy time is significantly longer in patients with PAD.

New guidelines for the diagnosis and management of pulmonary embolism: Key changes

Pulmonary embolism (PE) is an important public health problem. In August 2019, the European Society of Cardiology in collaboration with the European Respiratory Society released new guidelines for the diagnosis and management of PE. We discuss the basic changes between these recent guidelines and the previous guidelines that were published in 2014. Regarding diagnosis, the new guidelines propose the use of an age-adjusted cut-off level of D-dimers instead of a fixed cut-off value. A D-dimer test adapted to clinical possibility should also be considered instead of fixed cut-off level of D-dimer. Detailed recommendations for the diagnosis of PE during pregnancy are also provided. Regarding risk stratification, assessment of PE-related early mortality risk is recommended. Moreover, the importance of right ventricular dysfunction is emphasized in low-risk patients. For further risk stratification of the severity of PE in patients without hemodynamic instability, use of validated scores that combine clinical, imaging and laboratory PE-related prognostic factors might also be considered. Regarding treatment, the possibility of early discharge is mentioned in patients without severe comorbidities, who are not of high risk for sudden death and in whom proper medical management at home and proper medical follow up can be ensured. The new guidelines also suggest that pro-brain natriuretic peptide levels, right ventricular function and the presence of thrombus in the right heart could be useful for guiding the decision of early discharge. Overall, these new guidelines introduce several key changes and knowledge and adherence to them will improve the outcome of patients with PE.

The Role of Histone Modifications in the Pathogenesis of Diabetic Kidney Disease

Diabetic kidney disease (DKD) is the leading cause of chronic kidney disease. The pathogenesis of DKD is multifactorial, with several molecular pathways implicated. Recent data suggest that histone modification plays an important role in the development and progression of DKD. Histone modification appears to induce oxidative stress, inflammation and fibrosis in the diabetic kidney. In the present review, we summarize the current knowledge on the association between histone modification and DKD.

Effects of statin treatment in men and women with stable coronary heart disease: a subgroup analysis of the GREACE Study

BACKGROUND

Reducing low-density lipoprotein cholesterol (LDL-C) levels to National Cholesterol Expert Panel (NCEP) goal is recommended. However, sex-specific effects may influence benefit.

METHODS AND RESULTS

In this post hoc analysis of the GREek Atorvastatin and Coronary heart disease (CHD) Evaluation [GREACE] study we investigated the extent in vascular event reduction by statin treatment according to sex. From a total of 1600 patients with stable CHD, 624/176 and 632/168 were men/women on atorvastatin or on usual care, respectively. During 3-year follow-up, comparison of atorvastatin treatment with usual care demonstrated a relative risk reduction (RRR) of the primary end point (all vascular events) of 54% in women (hazard ratio [HR] 0.46, 95% confidence interval [CI] 0.24-0.87, p=0.003) and of 50% in men (HR 0.50, 95% CI 0.32-0.70, p<0.001). The fall in LDL-C levels played the key role in end point reduction in both sexes. However, in men there was an additional benefit related to the atorvastatin-induced increase in high density lipoprotein cholesterol (HDL-C) and estimated glomerular filtration rate (eGFR), while in women end points were related to a substantial triglycerides (TG) reduction.

CONCLUSIONS

Treatment with atorvastatin to the NCEP LDL-C goal compared with 'usual care' significantly reduced CHD morbidity and mortality in both men and women. Both men and women benefited from statin treatment possibly with different mechanisms making a contribution over and above LDL-C reduction.

Increased Sclerostin, but Not Dickkopf-1 Protein, Is Associated with Elevated Pulse Wave Velocity in Hemodialysis Subjects

BACKGROUND

Sclerostin and Dickkopf-1 (Dkk-1) proteins are inhibitors of the canonical Wnt/β-catenin bone pathway. Pilot data suggest that sclerostin may be involved in vascular changes in chronic kidney disease (CKD), but data on the effects of Dkk-1 are scarce. This is the first study investigating simultaneously the associations of sclerostin and Dkk-1 with arterial stiffness in hemodialysis patients.

METHODS

A total of 80 patients on chronic hemodialysis had carotid-femoral pulse wave velocity (PWV), central blood pressure (BP), and wave reflections evaluated with applanation tonometry (Sphygmocor) on a midweek non-dialysis day. Serum levels of sclerostin and Dkk-1 were measured with ELISA. A large set of demographic, comorbid, laboratory, and drug parameters were used in the analyses.

RESULTS

Subjects with PWV >9.5 m/s (high arterial stiffness group, n = 40) were older, had higher BMI, higher prevalence of hypertension, diabetes, and coronary heart disease, and higher peripheral systolic BP, central systolic BP, C-reactive protein, and serum sclerostin (p = 0.02), but similar Dkk-1, compared to subjects with low PWV. When dichotomizing the population by sclerostin levels, those with high sclerostin had higher PWV than patients with low sclerostin levels (10.63 ± 2.71 vs. 9.77 ± 3.13, p = 0.048). Increased sclerostin (>200 pg/mL) was significantly associated with increased PWV (>9.5 m/s; HR 2.778, 95% CI 1.123-6.868 per pg/mL increase); this association remained significant after stepwise adjustment for Dkk-1, intact parathyroid hormone, and calcium × phosphate product. In contrast, no association was noted between Dkk-1 and PWV (HR 1.000, 95% CI 0.416-2.403).

CONCLUSION

Serum sclerostin is associated with PWV independently of routine markers of CKD-MBD in hemodialysis patients. In contrast, Dkk-1 has no association with arterial stiffness and is not pathophysiologically involved in relevant vascular changes.

Increased augmentation index is paradoxically associated with lower in-hospital mortality in patients with acute ischemic stroke

OBJECTIVE

To evaluate the association between arterial stiffness and stroke severity and in-hospital outcome in patients admitted with acute ischemic stroke.

METHODS

We prospectively studied 415 consecutive patients who were admitted with acute ischemic stroke (39.5% males, age 78.8 ± 6.6 years). On the third day of hospitalization, the following markers of arterial stiffness were recorded: central systolic blood pressure (cSBP), diastolic BP (cDBP), mean pressure (cMP), pulse pressure (cPP), augmentation index (AIx) and pulse wave velocity (PWV). The severity of stroke was assessed on admission with the National Institutes of Health Stroke Scale (NIHSS) score. The outcome was evaluated with rates of dependency at discharge (modified Rankin scale score between 2 and 5) and in-hospital mortality.

RESULTS

None of the markers of arterial stiffness showed significant correlation with the NIHSS score on admission. However, there was a trend for an inverse correlation with AIx (r = -0.142, p = 0.064) and for a positive correlation with PWV (r = 0.235, p = 0.054). None of the markers of arterial stiffness differed between patients who were dependent at discharge and those who were independent. Patients who died during hospitalization had higher cDBP and cMP but lower cPP and AIx than patients who were discharged. In binary logistic regression analysis, independent predictors of in-hospital mortality were NIHSS score on admission (relative risk (RR) 1.16, 95% confidence interval (CI) 1.08-1.25, p < 0.001), presence of atrial fibrillation (RR 6.41, 95% CI 1.37-29.93, p = 0.018) and AIx (RR 0.94, 95% CI 0.89-0.99, p = 0.030).

CONCLUSIONS

Increased AIx appears to be associated with lower in-hospital mortality rates in elderly patients with acute ischemic stroke. Other markers of arterial stiffness do not appear to be associated with short-term outcome in this population.

Nonalcoholic Fatty Liver Disease vs. Nonalcoholic Steatohepatitis: Pathological and Clinical Implications

The implications and prognosis of nonalcoholic fatty liver (NAFL) and nonalcoholic steatohepatitis (NASH) are substantially different. The aim of the present review is to describe and compare the pathological and clinical implications of these two conditions. Patients with NASH have a higher risk of progressing to cirrhosis than patients with NAFL but without steatohepatitis, who tend to have a non-progressive disease and only a minority progresses to NASH. Patients with NASH also are at greater risk to develop hepatocellular cancer (HCC) and NASH is the third commonest cause of HCC. In contrast, only few cases of HCC have been reported in patients with isolated NAFL. Given that nonalcoholic fatty liver disease is the hepatic manifestation of metabolic syndrome, it is also strongly related to cardiovascular disease (CVD). Again, it appears that patients with NASH have higher cardiovascular risk than patients with NAFL. Finally, all-cause mortality is also higher in patients with NASH than in patients with NAFL; mortality rates in the latter patients do not differ from the general population. In conclusion, NAFL and NASH have different prognosis and therefore it is imperative to develop accurate, noninvasive methods that will identify the presence of steatohepatitis in this population.

A Comparative Assessment of Cardiovascular Autonomic Reflex Testing and Cardiac 123I-Metaiodobenzylguanidine Imaging in Patients with Type 1 Diabetes Mellitus without Complications or Cardiovascular Risk Factors

AIM

To compare the cardiovascular autonomic reflex tests (CARTs) with cardiac sympathetic innervation imaging with 123I-metaiodobenzylguanidine (MIBG) in patients with type 1 diabetes mellitus (T1DM).

PATIENTS AND METHODS

Forty-nine patients (29 males, mean age 36 ± 10 years, mean T1DM duration 19 ± 6 years) without cardiovascular risk factors were prospectively enrolled. Participants were evaluated for autonomic dysfunction by assessing the mean circular resultant (MCR), Valsalva maneuver (Vals), postural index (PI), and orthostatic hypotension (OH). Within one month from the performance of these tests, patients underwent cardiac MIBG imaging and the ratio of the heart to upper mediastinum count density (H/M) at 4 hours postinjection was calculated (abnormal values, H/M < 1.80).

RESULTS

Twenty-nine patients (59%) had abnormal CARTs, and 37 (76%) patients had an H/M_4 < 1.80 (p = 0.456). MCR, PI, Vals, and OH were abnormal in 29 (59%), 8 (16%), 5 (10%), and 11 (22%) patients, respectively. When using H/M_4 < 1.80 as the reference standard, a cutoff point of ≥2 abnormal CARTs had a sensitivity of 100% but a specificity of only 33% for determining CAN.

CONCLUSIONS

CARTs are not closely associated with 123I-MIBG measurements, which can detect autonomic dysfunction more efficiently than the former. In comparison to semiquantitative cardiac MIBG assessment, the recommended threshold of ≥2 abnormal CARTs to define cardiovascular autonomic dysfunction is highly sensitive but of limited specificity and is independently determined by the duration of T1DM.